THE RESEARCH PLAYBOOK
CONCLUSIONS Considerable variation in surface hardness was observed both within and between fields, with synthetic turf fields generally being harder than natural turfgrass fields. High-usage fields, regardless of surface type, were significantly harder than lowusage fields. Other surface metrics— such as rotational resistance, soil moisture, thatch depth and infill depth— also showed variability. On natural turfgrass fields, higher soil moisture was associated with lower surface hardness. On synthetic turf fields, increased usage reduced infill depth, which in turn increased surface hardness.
Although perfect field uniformity is not achievable, these findings emphasize how field usage and maintenance impact surface variability.
Additionally, our data suggest a potential relationship between surface hardness and mechanical load on athletes’ lower limbs. While this trend was evident, further research is needed to investigate its long-term health implications, particularly on surfaces that exceed acceptable hardness thresholds.
Survey data revealed that athletes rated the low-usage natural turfgrass field the highest, likely due to its softer surface and better aesthetics. In contrast, the high-usage natural turfgrass field, affected by poor maintenance and weed pressure, received the lowest ratings, underscoring the influence of field condition on athlete perception. These findings highlight the importance of field management and athlete feedback in evaluating and improving field quality.
Overall, this study provides valuable insights into how sports surfaces affect athletes. The results suggest that harder surfaces, such as synthetic turf or high-traffic areas, may increase impact and loading on the lower limbs. This reinforces the importance of effective field management and careful consideration of surface conditions prior to athletic competition.
Ava Veith is a graduate research assistant at Virginia Tech, and a former Division I soccer player at Virginia Tech; David McCall, Ph. D., is associate professor, Turfgrass Pathology and Precision Management, Virginia Tech; Chase Straw, Ph. D., is assistant professor of turfgrass soils and the director of the Center for Sports Surface Research, Penn State; Daniel Sandor, Ph. D., is collegiate assistant professor, Turfgrass Science, Virginia Tech; Jay Williams, Ph. D., is collegiate professor, Department of Human Nutrition, Foods, and Exercise, Virginia Tech; Elisabeth Kitchen is graduate research assistant, Virginia Tech; Kevin Hensler is senior research specialist, Virginia Tech; M. Aaron Tucker, Ph. D.; and Caleb Henderson, Ph. D.
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